1. Field of the Invention
The present invention relates to an abrasive grains classifying apparatus for classifying abrasive grains based on their sizes.
2. Background Art
Abrasive grains are classified based on their sizes using an abrasive grain classifying apparatus. The classified abrasive grains are attached to a base material to thereby manufacture a grinding stone (see, for example, JP-A-2005-279842 (FIG. 4)).
The prior art grinding stone as disclosed in JP-A-2005-279842 is described with reference to FIGS. 12A and 12B.
As shown in FIG. 12A, abrasive grains 202 are attached to an upper surface of a base material 201 through a plated layer 203.
As shown in FIG. 12B, leading ends of the abrasive grains 202 are cut to align heights of the abrasive grains 202, thereby manufacturing a grinding stone 205.
The inventors of the present invention have checked abrasive grains on the market for variations in their sizes. The check result has found that a grain diameter (for example, 200 μm) of an abrasive grain having the greatest grain diameter is two times or more than a grain diameter (for example, 50 μm) of an abrasive grain having the smallest grain diameter.
In order to align the heights of the abrasive grains, it is necessary to adjust the heights of the abrasive grains to the height of the abrasive grain having the smallest grain diameter. Therefore, in some cases, for the height adjustment, the abrasive grain having the largest grain diameter is cut by half or more.
That is, since projecting quantities of the abrasive grains from the base material are different from each other, there are inevitably generated the abrasive grains that are cut greatly, which results in waste cutting. If, in an abrasive grains classifying operation, the abrasive grains can be classified precisely, such waste can be avoided.
It is desired to provide an abrasive grains classifying apparatus which can manage sizes of the abrasive grains with high precision.